Does Hi-Lo Electric Cord Charge 12V Batteries?

[Lou M]

We own a 2007 Towlite 1907T that has 2 deep cycle Interstate 12V batteries. When we store the unit in our garage for months at a time, we want our batteries properly stored too. Unfortunately, our original Hi-Lo manual does not address this question, other than to state that batteries should be disconnected for storage. REALLY?

We were imagining that battery charging might be maintained by simply connecting the Hi-Lo electrical cord/plug to our garage outlet. But, some owners on this forum write about using trickle chargers.

Can we just plug into the garage outlet, or do we have to disconnect batteries and trickle charge?

 

[piperjim]

My converter does not charge the 12v battery. I suppose like so many things RV related, that feature increases the cost of production for the RV manufacturer, and they leave it off. On a previous RV, I added a Progressive Dynamics Charge Wizard that provided this function and would keep the on-board 12v battery charged when plugged into shore power, using what is known as "smart charger" capability that prevents sulfation of the battery. That converter had a built-in connector for the Charge Wizard and was easy to access. I use a trickle charger now and connect it to the RV battery every time I am at a camp site (we don't boondock) and keep it plugged in when at home.

Here's some info from RV Supplies, RV Accessories, RV Parts, Camper Parts, 5th Wheel Hitch

"Some models of RV converters are installed with a battery charging circuit which enables the 12 volt house batteries to be charged while the RV is plugged into shore power. Even though your convertor may be equipped with a battery charger it will not bring a completely dead battery back to life. RV converters do provide a charge to your RV house batteries, but only a small portion of the converters amperage rating is used for this. Normally 3 to 5 amps, which are not nearly enough to charge batteries that are discharged."

 

[Lou M]

Pipierjim:

Thanks much for the rapid reply and good info. I guess we'll just disconnect and trickle charge when in storage.

But, I have a related question also not addressed in my manual re the "Master Switch" that is a black-colored 3 position toggle with the following positions: "TOP ON," "MIDDLE OFF" and "LOWER ON." When towing, will the trailer batteries be charged by my truck's alternator when the 3-way switch is any of those 3 positions? Or, must this toggle be in a particular position for alternator charging to occur?

 

[piperjim]

I may be wrong, but I don't believe the position of the 3-way switch affects the RV battery charging from the alternator. Your problem isn't the switch, but the tow vehicle alternator and wiring. First, the alternator may not have the excess capacity, and second, the wiring on the vehicle may not be capable of carrying the amps needed to charge the battery.

The search function is your friend, although it's not the most user-friendly function on this forum.

Here's a thread to start you off:

http://www.hilotrailerforum.com/f28/trailer-battery-not-charging-while-traveling-4705/

Good luck!

 

[Lou M]

Yo Piperjim:

It looks like you were correctly reading my mind, as I have had trouble with drawn down trailer batteries (brand new, R24 in parallel) after towing with the refrigerator on DC. Your referral to the previous thread is a helpful start, so I'll get back to you when I know more. Off to the mines...

Thanks again.

Lou M

 

[piperjim]

Lou:

I've had that sinking feeling of arriving at a campground only to find the battery is stone dead, and then I having to manually pump the top of the RV into the up position. No fun!! So, I bought a pair of 12" or 18" lawnmower battery cables, and hooked them to the RV battery and ran the other ends outside of the battery compartment so I can clip on a set of jumper cables and use the tow vehicle battery to raise the top.....if necessary. The "hot" cable off the RV battery is wrapped in a piece of a swimming pool "noodle" so as to avoid it shorting out on the frame. That cable and pool noodle is secured with 2-3 zip ties. Once set up at the campground, I connect my trickle charger to those cables, which charges the RV battery. I also carry one of those nifty lithium battery packs, just in case. You can't have too much power!!!

 

[hilltool]

My converter DOES charge the batteries ( or, rather, there is a charger built into it), and I would think most hi-los from the eighties -on do. That said, I agree it doesn't do it well. I, Too, use a "smart charger" for the winter, and it gets cold up here in Wisconsin. I used to pull the batteries and stick them in the basement with the charger on but I now have storage with access to an outlet and go that route.

rick

 

[RichR]

You model has the converter/charger built in. It is probably an Elixor 35 amp model. It should get you charged up and maintain the charge. If it doesn't charge the batteries there could be a problem. Either the battery is shot or there is a problem with the converter like a blown fuse from being connected to the battery reverse polarity. A trickle charger is good for maintaining your charged batteries.

 

[amountaincreeker]

Lou, the last couple replies here are correct. Yours has the charger built in the converter so plugging it in will charge your batteries. I have a 2407T so we should have the same setup. Also, there is no charging position with the power switch in any position while in tow. It's not set up that way. Only way to charge while in tow would be of the solar type.

 

[JackandJanet]

Lou, the last couple replies here are correct. Yours has the charger built in the converter so plugging it in will charge your batteries. I have a 2407T so we should have the same setup. Also, there is no charging position with the power switch in any position while in tow. It's not set up that way. Only way to charge while in tow would be of the solar type.

I'm going to disagree with you regarding battery charging while in tow. If your tow vehicle is supplying power through the +12V line of a 7-pin plug, the trailer is receiving power from the tow vehicle's alternator, which is supposed to help keep the trailer battery charged. But, as has been stated many times in this forum, the wiring in the tow vehicle may be too small to carry the current needed, especially if you are running the trailer's refrigerator on DC while the trailer is under tow.

But, regarding the converter charging the battery when plugged into shore power, it should do it (or it's not a "converter"). If the converter is not producing DC power, its internal fuses are likely blown. See my recent thread on locating these "hidden" fuses and replacing them. Here's the link: http://www.hilotrailerforum.com/f28/converter-troubleshooting-repair-6454/

- Jack

 

[amountaincreeker]

Jack...this is the reply i see from E Trailer which is what my take is on it


The distance from the vehicle battery/alternator to the camper battery is too long to be able to charge up the camper battery. Going to larger wire will not help and can actually make it worse. Pushing back the required amount of amperage, not voltage, to charge up the battery would require a powerful alternator and large enough wire, like battery cable only maybe a little smaller, and it just isn't really feasible on a passenger vehicle.

The only sure way to charge up the trailer battery while you drive is to use a DC to DC charger, as an example, either connected to a 12 volt circuit in the trailer connector or to the vehicle alternator.

 

[thatguy-HILO]

I'm curious as well. Been thinking of going lithium and don't want any damage done to the Li battery during transit or by shore power charging (not sure mine has this or it's broken).

Li charging is very specific.

 

[Ranman55-HILO]

disconnect and use a trickle charger

 

[Lou M]

Dear Piperjim, Hilltool, RichR, Mountaincreeker, and JackandJanet,

Thanks so much for the great input. Our 1907T does have an Elixor converter, and it does appear to charge our two in-parallel batteries after we plug into an outlet. The Elixor converter is located under a driver-side seat box. I happened to notice it functioning, because its fan started whirring after we plugged in. It continued whirring into the first night, but by the next morning it had stopped, and it never again came on during our 5 night stay (while we were always plugged in).

We then headed home with the refrigerator running on DC, unloaded the trailer, turned off the refrigerator, and plugged the trailer into a garage outlet. The Elixor converter then started right up (fan whirring) and was off by the next morning, as seen previously. In summary, it appears that this Hi-Lo Model 1907T does have the capacity to charge its 12V batteries when it's plugged in to an AC source, and that's a good thing!

Now, if I can only figure out why the heater breaker keeps tripping....

 

[amountaincreeker]

Hey lou, just an FYI on running your fridge while in tow...On our last trip I found that 6 hours on the road was too much and the battery was dead when we got to the campground. However on a previous trip we did 4 hours so somewhere between may be the happy medium. Of course batteries will vary.

 

[JackandJanet]

amouuntaincreeker - I like etrailer and think they know what they are talking about in most cases but I don't totally agree with their advice regarding the wiring to the trailer plug in the tow vehicle. When I was researching and installing my trailer's solar panels, I found that the wiring needed to be quite heavy due to the high Amperage produced. 10 gauge was the minimum and if I'd wired my panels in parallel, which would have upped the Amperage, I'd have needed 8 gauge.

I'm pretty sure the wiring in my truck to the trailer plug is 12 gauge, which, due to the length, will not pass much current without developing a lot of resistance. So, replacing that with 10 gauge, would make more current available to the trailer.

However, the other factor - the output of the alternator is a major consideration and if the alternator can't produce more than the tow vehicle needs, then it can't possibly charge the trailer's batteries even with a heavier wire. I think that is also a limitation in some tow vehicles.

- Jack

 

[PyroJim]

There is an easy way to check the charging capability of your towing vehicle. All you need is a voltmeter. Hook your trailer up to the tow vehicle, but do not plug in the 7-pin electrical plug. Take your volt meter and check the voltage of your battery in your trailer. With the engine running in your tow vehicle, plug in the 7-pin electrical plug to the tow vehicle. You should see an increase in voltage. It might not be much, but if you see any increase, then the trailer battery is receiving a charge from the tow vehicle. Most factory wiring in tow vehicles is set up for anything for 10 to 20 amps of charging capacity from the tow vehicle which is more than enough to run your refer or just keep your battery topped off. To check to see if the 110 volt electrical cord is also charging the battery, do the exact same test: Check the voltage of the batteries, then plug in the 110 volt cord and check the voltage on the batteries again.

 

[JackandJanet]

PyroJim - I agree, and this is how I determined my converter was no longer charging the battery. If you see anything in the 13V or more range with the "charging" source active, then the battery IS receiving a charge.

But, if you are using the refrigerator on DC, it puts a huge draw on the battery when the refrigerator cooling is active and this can easily overcome the input from any DC charging source, including the tow vehicle and/or the converter. You'd have to verify the refrigerator is in a cooling cycle to see this effect. It would probably drop the voltage to 12.3V or less.

- Jack

 

[PyroJim]

Good point, Jack. Those refers can draw a lot. I'd do the voltage check with the refer off first. On a side note: There are a bunch of really cheap voltmeters on Ebay that plug into cigarette lighter sockets. I've seen them for 2 or 3 bucks and free shipping! It really makes this sort of simple troubleshooting easy. I put a cigatette lighter socket in my trailer to make charging the cell phone simple. I just put the voltmeter in there and I can always see the battery status.

PyroJim - I agree, and this is how I determined my converter was no longer charging the battery. If you see anything in the 13V or more range with the "charging" source active, then the battery IS receiving a charge.

But, if you are using the refrigerator on DC, it puts a huge draw on the battery when the refrigerator cooling is active and this can easily overcome the input from any DC charging source, including the tow vehicle and/or the converter. You'd have to verify the refrigerator is in a cooling cycle to see this effect. It would probably drop the voltage to 12.3V or less.

- Jack